What contributes to a boat's stability when having a flat bottom hull?

A flat bottom hull provides a stable platform on calm waters, but its stability can be further enhanced through various design elements. One key aspect is the addition of keels, which act as a form of lateral support. Keels help to resist side-to-side rolling motions by providing resistance against lateral forces, especially when the boat is subjected to waves or wind. This additional support is crucial for maintaining balance and stability, allowing the boat to perform better in challenging conditions.

The other options do not effectively contribute to stability in the context of a flat bottom hull. Weight distribution, such as additional weight at the bow, can affect the overall handling and comfort, but does not inherently create stability like a keel. Doubling the length of the boat might improve speed or reduce the impact of waves but does not directly correlate with stability in the same way keels do. Adding more electronic equipment may increase functionality but has no bearing on the physical stability of the hull in water. Thus, the addition of keels stands out as the primary factor enhancing the stability of a flat bottom hull.